04 LLY: loss of power, decline in fuel mileage and other

[dfenze]

Sorry about the long thread post, I am new to the forum and have issues that I do not know how to solve. 2004.5 LLY, 2500HD, 110K miles, K&N intake, MBRP 4" cat back exhaust, BullyDog outlook monitor, BullyDog triple dog programmer, ProComp leveling kit, BFG 285 A/Ts, ARB front bumper with Warn 12k winch.

1) While attempting to accelerate onto the freeway, I had NO power. RPM gage went up slightly and the turbo never spooled up. Eventually the turbo spun up and kicked in and truck took off. I observed lots of black smoke from pipe. I do have 3 EGR codes in. I also have a block plate and finger stick ready to install. Do I have a possible turbo issue? or would the block plate fix the issue? or do I need to pull the EGR, clean/fix it and then install the block plate? or is there something else?

2) Brand new and stock I was getting 450-500 miles/tank. After programmer, intake and exhaust install, I was getting ~375-450 miles/tank with a lot more power. Now, I am getting <300 miles/tank. I do have a P0101 code in. the MAF sensor has been cleaned, twice in the past 2 weeks. Fuel filter has been replaced. I run an injector cleaner/cetane booster every other tank. Suggestions?

3) Just replaced all 8 glow plugs and have a P0670 code. I have checked just about all of the wires and connections. They are good, from what I can see. will this module code have an effect on performance or just replace it anyway?

4) rough idle. Normal engine idle is 693. Mine is usually 660-693 and will sometimes go from 660-723. it never goes out of these bands. I do not know what to look at.

5) About to replace the ball joints, again. Is it normal for me to replace them twice at 110K?

I flashed the computer back to stock, but still have the Outlook monitor installed, since my inst cluster does not function correctly. (completely resets itself frequently, tach not work, speedo not always working, light bulbs out, etc...)
I feel that the engine is too 'young' to be having big issues. Any help/suggestions is greatly appreciated.

[DmaxMaverick]

Welcome aboard!

To start with, much of your upgrades will reduce your economy. I would suspect the totality to be significant. However, it shouldn't drop that much after a period of relatively good mileage with the mods.

You must do a few things (all at once) to get it to a baseline:
Get your codes cleared. The P0101 alone will reduce power and economy, and in many cases, cause the turbo to be very slow to respond. Combined with EGR issues, it is expected, actually.

Remove (physically) any and all aftermarket programming and power-adders.

Once this is done, establish an economy baseline. You'll need enough miles and time to develop a trend, and clean out the cat. I'll bet it will get you close to what you saw before, minus the hits from the tires, aerodynamic changes, and additional mass.

[dfenze]

ok. I will give it a try and post the results.

[DmaxMaverick]

Also, if you have any of those issues, it won't pass smog. Be careful what you "remove" when it's said and done. It also has to pass a visual inspection for any and all smog equipment. The inspectors are getting smarter every year, and learning what to look for.

[tx dave]

Thank goodness I have a 2001, with no smog junk. 300k, original brakes, original front end parts, shocks replaced twice, 4" exhaust, volant ram air, rebuild rearend at 125k. replaced motor at 175k with a used with 50k on it. I still love this truck and it drives like it did when I got it. I guess what I'm trying to say is there build to last. oh, paint job still shines like a new penny, thank to clay bar and new sinthetic wax ever 6 months. All that being said, I'm with dmax, go back to basics and start over, It reaally sound to me like one of your injectors is going south. What does it do if you turn it off and restart it?

[DmaxMaverick]

Thank goodness I have a 2001, with no smog junk......

The LB7 "smog" trucks are unique to CA and some N/E states. My 2001 CA truck has no smog equipment, same as yours. The "CA Emission" trucks began in 2002, with the addition of EGR, cat, and CA specific programming. My smog inspections are simple (but still cost the same), in that it's 100% visual. If the MIL isn't on, and it doesn't smoke excessively, it passes.